Improved bush for the sheaves of tackle-blocks



Specificatie forming part of` Lette `ZZ :whont` it. ma, `B it knownthat IysGHARLEs H. PLATT, of

the city, county,and State of` New York, have invented a "new and useful Improvement in, Metallic Bushesfo Wooden Sheaves; andl do herebydeclareithat the followingis a full, "clear, and exact `description of the same,A ref lerenee being `had 1 to the accompanying drawingsfmaking `ap 1i this specification, in which-f i' y )Figure lisa sic e` invention applied t Toa w` of a sheave with my i Fig. 2 is alsoa side 3 view of the `sainte', op` steto that shown in .Fig. `1`; Fig.` `3,a4 sect of the same, taken in the linelfwwF-i y 2; Fig.`4, a detached i e sideviewof he bush Fig.` 5, an end view of Fig.` 4;Fig`;"6`,faisi iewof a sheave pro- "vided withthe` y `metal bush.'

Similar letters o reference indicate corre- `several figures.

outer end wi it, Said b e "Annes RJPLATT, oF New YORK, `n. Y. IMPROVE* BUSH FORQTHESHEAvEsoF TAcKLE-BLocKs. t

rs Patent No. 35,622, dated June 17, 1862.

art c is of such a length that its ll be flush with the opposite side of the sheave, as shown clearlyin Fig. 3. The sheave A is mortised at its center, so as to receive snugly the part a of the bush. The flange b has two holes drilled through it at opposite points to allow bolts c c to pass through olts also passing t A. The heads d'of the bolts are let in the sheave at the `side opposite to that which receives the nange b, and the ends of the bolts are headed or riveted in the countersnnk holes of the iiange. In my improvement it bolts c c merely prevent the bush B from moving endwise out of the sheave; they are not intended to prevent the turning of the bnshin the sheave, for that end is attained by the squarelor polygonal part a., andas said bolts are not subjected to any strain they cannot the square p will be seen that the spondng lpartsin the y This invention y ists in having the greater portion oftheib `lich is fitted in the oodensheave `niad f` square uorpolygonal as hereinaftei escrbed, so as to effectuning of the bush Within epending on the bolts heflatter to" effect that allie4 bushesgare made of ylindrical fori re prevented from tu rnave `b"""pins or bolts which 'passe" bush and the sheave.

"n wear the sheave and e and thelatter is liahle y, to split.V `This d e, {1l/ty is fully obviated by `myinvention. i ,i i Y 'e Y Toenable those illed inthe art to fully l understand and construct my invention, I will proceed to describe it.

` A represen y e ts; a wooden sheave, and Bis `a 1 metallic bush `whichis fitted therein. This `bush B has lits largerlor` ma i square or"polygonalfform, as shown at a in Figs. 1, 4, `and 5,1th`e other portion, b, of the bushbeing largerin 'diameter than a and of shown clearly in Fig. 5. The .which maybe termed the e e e e heave, so` uter surface will be iiush with it, and

circular form, as part bof th f e e 'ilange, islet in" the side-of` the s that its c in portion made of `work loose in the sheave, and the latter there- 'fore will not be liable to split, as is the case with the ordinary metallic bush C, as shown `in Fig. 6. This bush G has its smaller part, y a', of cylindrical form, and consequently the .bolts c c', which pass throughits flange b', alone prevent it from turning in the sheave. These bolts c', owing to the strain to which they are subjected, in a short time work loose in the sheave and are liable to split it. When they get a little loose the wear rapidly increases, and in a short time the sheave works very imperfectly.

This invention is applicable to all wooden sheaves, whether inserted in blocks or used otherwise as ordinary pulleys.

Having thus described my invention, what I claiin as new,and desire to secure by Letters Patent, is-

A metallic bush, B, for wooden sheaves A, formed of a square or polygonal part, a, provided with a Iiange, b, of circular or other forin, to admit of the bolts c passingthrough it, substantially as and for the purpose set forth.V

Witnesses:

J AMES LAIRD, J. W. GooMBs.

hrough the sheave I cHAs. H. PLATT. e 

